Ingroup sources enhance associative inference

Episodic memory encompasses flexible processes that enable us to create and update knowledge by making novel inferences across overlapping but distinct events. Here we examined whether an ingroup source enhances the capacity to draw such inferences. In three studies with US-American samples (NStudy1 = 53, NStudy2 = 68, NStudy3 = 68), we investigated the ability to make indirect associations, inferable from overlapping events, presented by ingroup or outgroup sources. Participants were better at making inferences based on events presented by ingroup compared to outgroup sources (Studies 1 and 3). When the sources did not form a team, the effect was not replicated (Study 2). Furthermore, we show that this ingroup advantage may be linked to differing source monitoring resources allocated to ingroup and outgroup sources. Altogether, our findings demonstrate that inferential processes are facilitated for ingroup information, potentially contributing to spreading biased information from ingroup sources into expanding knowledge networks, ultimately maintaining and strengthening polarized beliefs.

18th Aug 23 Dear Dr Bramao, Thank you for your patience during the peer-review process.Your manuscript titled "Inferential memory is moderated by the ingroup/outgroup status of the information source" has now been seen by 2 reviewers, and I include their comments at the end of this message.They find your work of interest, but raised some important points.We are interested in the possibility of publishing your study in Communications Psychology, but would like to consider your responses to these concerns and assess a revised manuscript before we make a final decision on publication.
We therefore invite you to revise and resubmit your manuscript, along with a point-by-point response to the reviewers.Please highlight all changes in the manuscript text file.
Editorially, we note that both reviewers are asking for more justification about key experimental decisions including sample size, the motivation for each experiment, and various analytical choices (e.g., how is team source memory specified?what was the rationale for looking at partial source memory?).Reviewer #2 provides guidance to steer away from calling non-significant results "marginal" and instead provide Bayes factors for what you deem to be "marginal" effects.These requests are in line with the journal's requirements for statistics reporting and interpretation as detailed in the checklist and template linked below (under EDITORIAL POLICIES AND FORMATTING).
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REVIEWERS' COMMENTS:
Reviewer #1 (Remarks to the Author): The study investigated how memory for object-scene pairs (AB) is affected by ingroup/outgroup status of a "persona" presented alongside them, as well as how the ingroup/outgroup status affects the likelihood of episodic inference that connects those AB associations with overlapping BC associations (AB & BC, therefore AC).The results showed that participants better remember objectscene AB associations and better inferred AC relationships when the AB associations were "presented" by an ingroup persona than outgroup persona.There was a flip side to this effect as the source memory (memory who presented a given object) was worse for ingroup than outgroup source.These findings provide an interesting connection between previously separate lines of research on episodic inference with research on source identity memory effects, and allude to how our biases towards information from ingroup sources may affect not only memory for individual information but also our tendency to connect related memories in service of knowledge formation.
This was a refreshing paper to read and a review to write.There was a lot to like.The studies were well designed, two studies were pre-registered, the authors self-replicated Study 1 in Study 3 after not finding an effect with a different manipulation in Study 2. The analyses were appropriate, results were interesting, the conclusions were well supported and carefully worded.Finally, the whole paper was very well written.It seems like a lot of thought went into each analysis decision as well as how much and where to report (e.g., adding Bayesian statistics when appropriate, including follow up exploratory analyses to corroborate some of the results).
I only have a few points I would like to see addressed.
1. Team source memory?One important set of findings related to team source memory, but it's not possible to evaluate those as written.There needs to be more clarity and details for the methods, especially how it's even possible to get the "team" correct but persona incorrect in a 2-alternative forced-choice test.As written and visualized in Fig 1, there were only two personas to choose from on every trial.Presumably, one of them was correct but the nature of the foil is not explained.If it's always a persona from another team, then it wouldn't be possible to choose a wrong persona from a correct team.If the foil can be from the same team as the correct choice (on some percentage of trials?), then essentially both answers are correct when analyzing for "team" source correct score, so it's again not possible to compare 100% sure correct options across conditions, unless "?" (don't know) responses are counted as incorrect on those trials.Either way, this needs to be much clearer.
2. AB effect driving AC effect?With one exception, all AC differences were accompanied by AB differences.It would be important to know if the AB differences fully account for AC differences or if AC differences go above and beyond AB differences.Are people unable to make AC inference because they don't remember the AB trials?Or are there additional inference effects even after AB's were taken into account.There is probably many ways how to address this question.For instance, Zeithamova and Preston 2017 did two control analyses when faced with the same issue of AC differences being potentially driven by AB differences, one looking at across-subjects correlations, one limiting AC analysis to only those trials where AB was remembered.Just to clarify, the paper is still a worthwhile reading, even if it turns out that the AC differences can be fully explained by AB differences.
3. In the discussion, the authors provide an example that concludes: "Our results suggest that you would be less likely to attribute this to the fundraiser of the disliked group than if your own group had been responsible."I was confused about this claim and did not find it consistent with the data.All the source memory effects (for team) were driven by lower Ingroup Incorrect Inference trials, with the remaining conditions (outgroup correct and incorrect AC, ingroup correct AC) being all about equal.Either revise the example or provide a more thorough handholding through the logic of your claim.
4. Detail memory.Detail memory was delegated to the supplement because no effects were found, which is fine.However, given the Carpenter & Schacter vs. de Araujo Sanches & Zeithamova conflicting findings, the null effect may be actually interesting.I would definitely like to see more information, even if it remains in the supplement.At minimum, please report the actual data with the actual error magnitude for each condition (not just anova results).I also didn't understand the scaling to values between 0 and 1 and how that would help with large variability, unless it's a nonlinear conversion.Nevertheless, using analyses on each subject's medians instead of means seemed like an appropriate choice given that the error distributions are necessarily very skewed.

Minor comments:
-Fig 1 legend: "In Study 3, the items were assessed ..".Maybe switch to "the personas" to avoid confusion with objects?-Why were the subjects US-Americans when the research team isn't?-Provide age range in addition to the mean age for participants in all studies Reviewer #2 (Remarks to the Author): This manuscript investigated the effects of ingroup vs. outgroup status of information source on memory for inferential associations in three studies.In all studies, participants were first shown an object picture on a background image (AB) that was presented by a persona whose views/interests were similar vs. dissimilar to their own (ingroup vs. outgroup), and then a different object picture on the same background image (BC).Later, participants' memory for indirect, associative inferences (AC), direct associations (AB, BC), as well as for the information source (source memory: whether an object was presented by ingroup or outgroup) and the location (detail memory) of the individual objects were probed.Studies 1 and 3 used two personas per group, whereas Study 2 had only one persona per group.In Studies 1 and 2, interpersonal liking as a manipulation check was measured once on a relative scale (with the ingroup at one end of the scale and the outgroup at the other), whereas in Study 3 it was measured separately per each group.In all studies, participants liked ingroup personas more than outgroup personas.Also consistent across the studies, memory was better for direct AB, BC associations than for associative AC associations.Of direct relevance to this manuscript's inquiry, in Studies 1 and 3, there was an ingroup advantage in associative AC inference (as well as in memory for AB and BC associations).Also, in Study 1, source memory was better following successful than unsuccessful associative inference, but only for ingroup trials but not for outgroup trials, with outgroup source memory significantly better than ingroup source memory following successful inference.These source memory results were largely replicated in Experiment 3, with a caveat that some of the comparisons did not reach statistical significance.In comparison to these results from Studies 1 and 3, in Study 2, the authors found no significant effect of group on associative AC inference, direct AB and BC associations, or source memory.This is an interesting paper that addresses an empirical question of how social group membership influences memory integration.It is a nice extension of previous studies on the effects of social group membership on memory processes, and the findings of this study will be informative for future studies aimed at investigating specific proximal mechanisms through which the perception of ingroup vs. outgroup affects everyday memory processes.The studies appear to have been competently designed and conducted, the statistical analyses are appropriate to the research question, and the findings are clearly reported.Overall, I found the manuscript well-organized and well-written.However, I have a number of suggestions for improving the manuscript that I list below, roughly in the order they appear in the manuscript.
The authors describe that their sample size for Study 1 was based on the sample size in previous studies but these studies they mention appear to bear no relevance to the critical ingroup vs. outgroup manipulation.Furthermore, the authors make no mention at all of power or expected effect sizes.Did the authors consult any past studies that looked at the effects of social group on memory processes (e.g., Jeon et al., 2021;Marsh, 2020 that the authors themselves cite in the manuscript)?Was the sample size of Study 1 sufficient to detect ingroup-related memory effects reported in such studies?In fact, given that this manuscript is concerned with memory for indirect, inferential associations rather than direct associations, the authors should expect their effect sizes to be somewhat smaller than the effect sizes reported in previous memory studies.In any case, I suggest that the authors offer an improved rationale for the sample size for Study 1.
There appears to be some room for improvement in terms of describing questions motivating Studies 2 and 3.For example, in Study 2, the authors briefly mention that they wanted to see if it is liked individuals vs. ingroup that gives rises to the ingroup advantage in associative inference, but provide no description at all about relevant background literature and/or hypotheses.Likewise, in Study 3, the authors describe that they chose to measure interpersonal liking separately for each group (rather than once using a relative scale as in Studies 1 and 2) in order to examine a potential correlation between the ingroup advantage in associative inference and ingroup liking, but to me it is not very clear why the relative scale could not be used to test for the correlation.I suggest the authors to further elaborate on the motivation/rationale for each study to improve their already well-written manuscript even further.
Across both the main text and the supplementary material, there are a good number of analyses that the authors performed, but without providing clear justification (e.g., categorizing trials based on the ease of encoding for source memory analysis, partial source memory analysis).For example, it is not very clear why the authors decided to look at partial source memory, and how the results of partial source memory relate to ingroup vs. outgroup inferential success and/or to the absence of ingroup advantage in associative inference when there is only one persona (in Study 2).I suggest the authors to provide a clearer justification/explanation for why they made certain analytical choices and discuss the results of different analyses in light of the main inquiry of the manuscript.This will greatly help the reader to more clearly follow the results from each separate analysis and to better understand their implications.
For the sake of completeness, I would like to ask the authors to report Bayes factors (i.e., "amount of evidence") for not only null effects but also significant effects consistently throughout the manuscript.On a related note, I suggest the authors to steer away from calling non-significant results as "marginal" and provide Bayes factors for what they deemed "marginal".Doing so will allow the reader to gauge the amount of evidence for the reported non-significant results (and any follow-up planned comparisons that were done despite the non-significant null effect).
In the discussion, the authors state "The higher source monitoring resources allocated to the outgroup may interfere with encoding the episode itself, leading to lowered mnemonic flexibility for outgroup information.This is different for trustworthy ingroup information where the encoding of the source may be secondary to the episode itself."(on p. 20).To me this is difficult to follow: if what the authors suggest is the case, shouldn't source memory for outgroup trials better following incorrect than correct AC inferences (i.e., incorrect AC inferences resulting from even greater interference with encoding the episode itself due to outgroup source monitoring)?Likewise, if encoding of the ingroup source was secondary to the encoding of the episode itself, then why source memory for ingroup trials were found to be better following correct than incorrect AC inferences?Shouldn't source memory for ingroup trials be generally low regardless of AC inference success?All in all, it was difficult to follow the authors' discussion of the source memory results, and I suggest that the authors to elaborate more on their discussion of the differing ingroup vs. outgroup source memory pattern and how this difference may relate to differential inferential success.
On p. 20, the authors suggest that "The enhanced encoding of ingroup information (e.g., Jeon et al., 2020;Marsh, 2020) may have boosted" both encoding-and retrieval-related mechanisms underlying successful inferences.This suggestion raises the question of whether the ingroup advantage observed for memory for AB associations contributed to the ingroup advantage in associative AC inference.I recommend that the authors incorporate the results from relevant analyses addressing this question in their revision, in the main text if space allows.There were a few errors: -"Outgroup source memory was higher for unsuccessful inferences" (on p. 20): Outgroup source memory was not significantly affected by inferential success, so this sentence was hard to follow.Perhaps, the authors wanted to say that outgroup source memory was better than ingroup source memory following unsuccessful inferences?Please clarify.
-"Even though the ABs were not directed associated with a social identity, these associations can come to mind during BC encoding […]" (on p. 26): It is difficult to understand what the authors are saying here.Did I miss anything?Weren't all ABs presented with an ingroup or outgroup persona?

Response Letter to Reviewers Reviewer 1
The study inves gated how memory for object-scene pairs (AB) is affected by ingroup/outgroup status of a "persona" presented alongside them, as well as how the ingroup/outgroup status affects the likelihood of episodic inference that connects those AB associa ons with overlapping BC associa ons (AB & BC, therefore AC).The results showed that par cipants be er remember objectscene AB associa ons and be er inferred AC rela onships when the AB associa ons were "presented" by an ingroup persona than outgroup persona.There was a flip side to this effect as the source memory (memory who presented a given object) was worse for ingroup than outgroup source.

This was a refreshing paper to read and a review to write. There was a lot to like. The studies were well designed, two studies were pre-registered, the authors self-replicated Study 1 in Study 3 a er not finding an effect with a different manipula on in Study 2. The analyses were appropriate, results were interes ng, the conclusions were well supported and carefully worded. Finally, the whole paper was very well wri en. It seems like a lot of thought went into each analysis decision as well as how much and where to report (e.g., adding Bayesian sta s cs when appropriate, including follow up exploratory analyses to corroborate some of the results).
We thank the reviewer for the encouraging evalua on of our manuscript.

Team source memory? One important set of findings related to team source memory, but it's not possible to evaluate those as wri en. There needs to be more clarity and details for the methods, especially how it's even possible to get the "team" correct but persona incorrect in a 2-alterna ve forced-choice test. As wri en and visualized in Fig 1, there were only two personas to choose from on every trial. Presumably, one of them was correct but the nature of the foil is not explained. If it's always a persona from another team, then it wouldn't be possible to choose a wrong persona from a correct team. If the foil can be from the same team as the correct choice (on some percentage of trials?), then essen ally both answers are correct when analyzing for "team" source correct score, so it's again not possible to compare 100% sure correct op ons across condi ons, unless "?" (don't know) responses are counted as incorrect on those trials. Either way, this needs to be much clearer.
We thank the reviewer for drawing our a en on to this important issue and the need for a more detailed descrip on.We have now clarified the methods of both Study 1 (p.26) and Study 2 (p.30).In the memory source test of Study 1 and 3, par cipants were presented with all four personas and were asked to select the accurate one.This setup enables differen a on between persona-based and teambased source memory.In Study 2, however, with only two personas presented, discerning between source memory for the team and persona it is not possible.We have updated Figure 1, which now displays the procedure of Study 1 and 3, where par cipants had to iden fy the source among all four personas.

AB effect driving AC effect? With one excep on, all AC differences were accompanied by AB differences. It would be important to know if the AB differences fully account for AC differences or if AC differences go above and beyond AB differences. Are people unable to make AC inference because they don't remember the AB trials? Or are there addi onal inference effects even a er AB's were taken into account. There is probably many ways how to address this ques on. For instance, Zeithamova and Preston 2017 did two control analyses when faced with the same issue of AC differences being poten ally driven by AB differences, one looking at across-subjects correla ons, one limi ng AC analysis to only those trials where AB was remembered. Just to clarify, the paper is s ll a worthwhile reading, even if it turns out that the AC differences can be fully explained by AB differences.
We concur with the reviewer that this is a valuable point to address.Following the sugges on, we tested if the ingroup advantage observed in ABs predicted the ingroup advantage observed in the ACs in Studies 1 and 3.For completeness, we also tested if the ingroup advantage observed in BCs (in Study 3) could predict the ingroup advantage in the ACs.Interes ngly, we found that the ingroup advantage observed in direct associa ons did not predict indirect associa ons, sugges ng that the inference ingroup advantage is not merely a func on of the previously reported direct ingroup advantages.These analyses and findings have been incorporated into the main manuscript (see p. 9 and p. 16f), with a further discussion of the ma er on p. 21.

In the discussion, the authors provide an example that concludes: "Our results suggest that you would be less likely to a ribute this to the fundraiser of the disliked group than if your own group had been responsible." I was confused about this claim and did not find it consistent with the data. All the source memory effects (for team) were driven by lower Ingroup Incorrect Inference trials, with the remaining condi ons (outgroup correct and incorrect AC, ingroup correct AC) being all about equal. Either revise the example or provide a more thorough handholding through the logic of your claim.
We appreciate the reviewer's comment and have revised the example in the text.The example aims to illustrate that we are more likely to make inferences across event boundaries if the informa on is provided by an ingroup source.Our findings suggest that we are more inclined to a ribute the cleanliness (C) of the park (B) to the fundraiser (A) if arranged by an organiza on we like or are part of compared with an organiza on we dislike (p.19f.).We believe that the revised example provides a clearer reflec on of the associa ve inference task and more seamlessly illustrates the poten al implica ons of our findings.

Detail memory. Detail memory was delegated to the supplement because no effects were found, which is fine. However, given the Carpenter & Schacter vs. de Araujo Sanches & Zeithamova conflic ng findings, the null effect may be actually interes ng. I would definitely like to see more informa on, even if it remains in the supplement. At minimum, please report the actual data with the actual error magnitude for each condi on (not just anova results). I also didn't understand the scaling to values between 0 and 1 and how that would help with large variability, unless it's a nonlinear conversion. Nevertheless, using analyses on each subject's medians instead of means seemed like an appropriate choice given that the error distribu ons are necessarily very skewed.
We have added descrip ve values for detail memory for each condi on and study to Supplementary Note 4. These can be consulted in Supplementary Table 4.1.We have also clarified the scaling.The problem of high variance was only tackled by using medians for each par cipant, while the scaling was merely applied to make values more easily interpretable.The raw values were in screen size units from Pavlovia and higher values indicate a bigger difference between actual and indicated object posi on.We therefore scaled and flipped the values so that values of 1 would indicate the best detail memory (p. 9 of Supplement).

Minor comments: -Fig 1 legend: "In Study 3, the items were assessed ..". Maybe switch to "the personas" to avoid confusion with objects?
We have clarified this ambiguous formula on in the legend of Figure 1 (p.7).

-Why were the subjects US-Americans when the research team isn't?
Poli cal orienta on was the first a ribute that par cipants had to assign to the personas, providing a sort of anchoring for the rest of the profile construc on.Sweden, where our research team is located, is a mul -party democracy with eight par es currently represented in parliament.This would have made the group manipula on, where par cipants assigned party membership to the personas, less clear-cut, as differences between most par es are generally less prominent.We therefore decided to use the US, that has a two-party system with strong polariza on (Huddy et al., 2018), to gather trac on in the group manipula on.As this is a ques on that may be interes ng for readers, we have added some informa on on this issue in the Par cipants sec on of Study 1 (p.22).

-Provide age range in addi on to the mean age for par cipants in all studies.
We thank the reviewer for no cing that this was absent from the text.This informa on is now added (pp. 22, 29, 30).

This is an interes ng paper that addresses an empirical ques on of how social group membership influences memory integra on. It is a nice extension of previous studies on the effects of social group membership on memory processes, and the findings of this study will be informa ve for future studies aimed at inves ga ng specific proximal mechanisms through which the percep on of ingroup vs. outgroup affects everyday memory processes. The studies appear to have been competently designed and conducted, the sta s cal analyses are appropriate to the research ques on, and the findings are clearly reported. Overall, I found the manuscript well-organized and well-wri en. However, I have a number of sugges ons for improving the manuscript that I list below, roughly in the order they appear in the manuscript.
We thank the reviewer for these posi ve comments about our studies and manuscript.
The authors describe that their sample size for Study 1 was based on the sample size in previous studies but these studies they mention appear to bear no relevance to the critical ingroup vs. outgroup manipulation.Furthermore, the authors make no mention at all of power or expected effect sizes.Did the authors consult any past studies that looked at the effects of social group on memory processes (e.g., Jeon et al., 2021;Marsh, 2020

that the authors themselves cite in the manuscript)? Was the sample size of Study 1 sufficient to detect ingroup-related memory effects reported in such studies? In fact, given that this manuscript is concerned with memory for indirect, inferential associations rather than direct associations, the authors should expect their effect sizes to be somewhat smaller than effect sizes reported in previous memory studies. In any case, I suggest that the authors offer an improved rationale for the sample size for Study 1.
We thank the reviewer for this observation.We also consulted studies that evaluated the effect of social group on memory.These studies typically have samples sizes of around 50 (Jeon et al., 2021;Xia et al., 2019) and they often use other paradigms and designs, such as social contagion paradigms with only a handful of trials (Andrews & Rapp, 2014), or between-subject designs (Marsh, 2020).Therefore, we believe that studies investigating associative inference mirrored our design more closely (Carpenter & Schacter, 2017).However, in agreement with the reviewer suggestion, we now provide an elaborated rationale for our sample size that also refers to studies investigating effects of social group on memory (p.22).Given that this study was the very first one investigating this effect, we decided to be conservative and open 60 slots, also not knowing how big the drop out would be in the online setting.

There appears to be some room for improvement in terms of describing questions motivating Studies 2 and 3. For example, in Study 2, the authors briefly mention that they wanted to see if it is liked individuals vs. ingroup that gives rises to the ingroup advantage in associative inference, but provide no description at all about relevant background literature and/or hypotheses.
We thank the reviewer for this comment and have expanded the introduction of Study 2 to clarify our reasoning (p.14).The attempted replication with one persona per group was based on the social memory literature, which often tests the effect not only with ingroup members within an explicit group framework, but also with liked, trusted, or known individuals, often finding similar effects.We therefore decided to test if the social effects in inferential memory would also generalize to liked individuals (instead of groups).

Likewise, in Study 3, the authors describe that they chose to measure interpersonal liking separately for each group (rather than once using a relative scale as in Studies 1 and 2) in order to examine a potential correlation between the ingroup advantage in associative inference and ingroup liking, but to me it is not very clear why the relative scale could not be used to test for the correlation. I suggest the authors to further elaborate on the motivation/rationale for each study to improve their already well-written manuscript even further.
We are grateful to the reviewer for this very relevant comment.The rationale for the use of separate liking scales has now been clarified in the introduction of Study 3 (p.15f).The use of the separate scales made it possible to obtain independent measures for ingroup liking and outgroup disliking, creating alignment with the conventional use of liking measures like the IL-6 that we used (Veksler & Eden, 2017).First, the separate scales improved the group manipulation check, as we could now analyze not only relative ingroup preference but also whether the manipulation induced both ingroup like and outgroup dislike.Second, we expected this assessment to be less taxing for participants as they did not have to compare between personas while making judgements.We leveraged this improved assessment to test whether the AC ingroup advantage would co-vary with the liking ingroup bias in order to bolster the connection between the social group manipulation and the observed inference effect.
Across both the main text and the supplementary material, there are a good number of analyses that the authors performed, but without providing clear justification (e.g., categorizing trials based on the ease of encoding for source memory analysis, partial source memory analysis).For example, it is not very clear why the authors decided to look at partial source memory, and how the results of partial source memory relate to ingroup vs. outgroup inferential success and/or to the absence of ingroup advantage in associative inference when there is only one persona (in Study 2).I suggest the authors to provide a clearer justification/explanation for why they made certain analytical choices and discuss the results of different analyses in light of the main inquiry of the manuscript.This will greatly help the reader to more clearly follow the results from each separate analysis and to better understand their implications.
We thank the reviewer for noticing that some aspects of the analysis lacked a clear rationale.First, we have now clarified the categorization of the trials for the analysis (see Supplementary Note 2, p. 4).Second, we have also provided the rationale for the partial source memory analysis (p.26f of the manuscript and Supplementary Note 5 p. 11).This analysis was conducted to check our group manipulation.Previous studies have showed that outgroup is associated with lower individualization (Brewer et al., 1995;Crump et al., 2010).Thus, we tested if this was evident also in our experiment, using the partial source memory indicator.This was the case, supporting the success of the manipulation.To make this clearer we now present this analysis together with the manipulation checks.

For the sake of completeness, I would like to ask the authors to report Bayes factors (i.e., "amount of evidence") for not only null effects but also significant effects consistently throughout the manuscript. On a related note, I suggest the authors to steer away from calling non-significant results as "marginal" and provide Bayes factors for what they deemed "marginal". Doing so will allow the reader to gauge the amount of evidence for the reported non-significant results (and any follow-up planned comparisons that were done despite the non-significant null effect).
We thank the reviewer for this comment.We have removed all references to "marginal effects".Instead, Bayes factors are presented for all the effects that were deemed "marginal".

In the discussion, the authors state "The higher source monitoring resources allocated to the outgroup may interfere with encoding the episode itself, leading to lowered mnemonic flexibility for outgroup information. This is different for trustworthy ingroup information where the encoding of the source may be secondary to the episode itself." (on p. 20). To me this is difficult to follow: if what the authors suggest is the case, shouldn't source memory for outgroup trials better following incorrect than correct AC inferences (i.e., incorrect AC inferences resulting from even greater interference with encoding the episode itself due to outgroup source monitoring)? Likewise, if encoding of the ingroup source was secondary to the encoding of the episode itself, then why source memory for ingroup trials were found to be better following correct than incorrect AC inferences? Shouldn't source memory for ingroup trials be generally low regardless of AC inference success? All in all, it was difficult to follow the authors' discussion of the source memory results, and I suggest that the authors to elaborate more on their discussion of the differing ingroup vs. outgroup source memory pattern and how this difference may relate to differential inferential success.
We appreciate that the reviewer highlights that the discussion concerning source memory patterns across ingroup and outgroup was unclear.The interpretation of our findings is focused on situations when encoding is difficult, in which participants need to prioritize which information to encode.When encoding is difficult, the ingroup sources may be sacrificed for episode information, while outgroup sources take dominance over episodic information.Under easy encoding conditions, it is more likely that the whole episode is encoded and no differences between ingroup and outgroup source are expected to be observed.This interpretation is corroborated by the analysis presented in the Supplementary Note 2. Here, we show that difficult encoding circumstances that still lead to correct AC inferences are associated with a loss of source information for the ingroup.However, the source of outgroup information is kept, even under difficult encoding circumstances.We have now substantially revised the text about the source memory in the discussion of Study 1 (p.11) and in the main discussion (p.20), making it clearer that the interpretation is focused on variation in encoding difficulty.

On p. 20, the authors suggest that "The enhanced encoding of ingroup information (e.g., Jeon et al., 2020; Marsh, 2020) may have boosted" both encoding-and retrieval-related mechanisms underlying successful inferences. This suggestion raises the question of whether the ingroup advantage observed for memory for AB associations contributed to the ingroup advantage in associative AC inference. I recommend that the authors incorporate the results from relevant analyses addressing this question in their revision, in the main text if space allows.
We thank the reviewer for this valuable suggestion.We ran the proposed analyses and found no evidence that the ingroup biases effect found in the AB/BC direct associations predicts the AC indirect inference.These analyses and results have been incorporated into the text (see p. 9 and p. 16f).See also comment to Reviewer 1.

There were a few errors:
-"Outgroup source memory was higher for unsuccessful inferences" (on p. 20): Outgroup source memory was not significantly affected by inferential success, so this sentence was hard to follow.Perhaps, the authors wanted to say that outgroup source memory was better than ingroup source memory following unsuccessful inferences?Please clarify.We thank the reviewer for spotting this mistake.They are absolutely right, and this sentence was missing the qualification that it was higher than the ingroup for unsuccessful inferences.We have corrected this error (p.20).

-"Even though the ABs were not directed associated with a social identity, these associations can come to mind during BC encoding […]" (on p. 26): It is difficult to understand what the authors are saying here. Did I miss anything? Weren't all ABs presented with an ingroup or outgroup persona?
Once again, we thank the reviewer for pointing out this error -it is indeed the BCs that were not directly associated with a social identity, not the ABs (now on p. 27).
2nd Nov 23 Dear Dr Bramao, Your manuscript titled "Inferential memory is moderated by the ingroup/outgroup status of the information source" has now been seen by our reviewers, whose comments appear below.In light of their advice I am delighted to say that we are happy, in principle, to publish a suitably revised version in Communications Psychology under the open access CC BY license (Creative Commons Attribution v4.0 International License).
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